Electrical selector



Dec. 5, 1933.

H. L. BLACK 1,938,213

ELECTRICAL SELECTOR Filed March 30, 1929 T0 TRANSLATING pfV/CE 68 4 7 63 gwuentom Harr IbBlach,

Patented Dec. 5,1933

1 j UNITED sTATEs PATENT o EFlcE 1,938,213 ELECTRICAL S LECTOR Barry L. Black, Toronto, Ontario, Canada Application March so, 1929. Serial No. 351,421

3 Claims. (01. 177-353) This means relates to electrical selectors,that is, to means whereby an operator or automatically operated means, located at a control point, may complete a circuit to any one of a multiplicity of electrically operated devices, included in any given system of such devices, to the exclusion of all other such devices in the system.

An object of the invention is to provide an electrical selector inclusive essentially of polarized relays adapted for a combination of local battery and line circuit operation, whereby they are effective by changing thepolarity of the line current to complete a line or local circuit to a related" device. As a result the present selector is positive in operation, as distinguished from the uncertain functioning of electro-mechanical selectors and selectors employing'the dot and dash method of selection, and is capable of being operated at maximum speed. 1

1 Another object of the invention is to provide an electrical selector which is extremely flexible in its arrangement-so thatby onlyrninor alterations and additions thereto the number of electrically operated devices which may be included 7 duplicates of one another, to enable a maximum number of electrically operated devices to be included in a system employing the present selec-t tor for their control, thus to minimize'installa tion, operation and maintenance costs.

With the foregoing general purposes in view,

the invention consists in the novel combination, connection and relative arrangement of parts as will be hereinafter more fullydescribed, illustrated in the accompanying drawing and defined in the appended claims.

In the drawing, the figure is a diagrammatic illustration of an electrical selector embodying parts arranged and connected together in accordance with the present invention.

In the example of the invention illustrated in the drawing, A, B and C designate, respectively,-

three polarized relays, that is, relays inclusive of permanent magnets whereby their switch operating armatures are actuated, not alone by energization and deenergization 0f the relay coils,

soft iron cores whereby their armatures are operated only by energization and deenergization of their coils and are'unaifected by changes in the polarity of the current with which they are energized. For convenience, the relays A, B and 60.

C may be called counting relays; and relays A, B and C may be called register relays.

The polarized relay A in the present instance is inclusive of three switch-arms designated 1, 2' and 3, respectively, for cooperation with contacts 1 2 and 3 respectively, the contact 1 being a back contact whereby it is in engagement with the switch arm 1 when the relay is deenergized, and the contact 2*, being a front contact whereby its related switch arm 2 is engaged therewith only when the relay is energized. The contact arms 1 and 2 are neutral contact arms affected solely by energization' and deenergization of the relay, While contact arm 3 is a polar contact arm affected by changes in the polarity or direction of the current with which the relay is energized. I i

The polarized relay B in the present instance isinclus'ive of three switch arms designated 4, Sand 6, respectively, the first of which is adapted vfor cooperation with a back contact 4 the second of which is adapted for cooperation with both back and front contacts designated 5, 5*, respectively, and the third of which, the polarized switch arm, is adapted for cooperation with a contact 6.

The polarized relay C in the present instance is inclusive of a pair of switch arms 8 and 9, respectively, thefirst of which is adapted for cooperation with a front contact 8 'and a back contact 8 and the second of which, the polarized switch arm, is adapted for cooperation with a' 0 contact 9 v i The neutral relay A is inclusive in the present instance of five switch arms designated 10, 11, 12,

13and 14, respectively, the first'of which is adapted for cooperation with a front'conta'ct 10, the second ofwhich is adapted for cooperation with a back contact 11, the third of which is adapted for cooperation with a back contact 12*, the fourth of which is adapted for cooperation with a front contact 13, and the fifth of which is adapt ed for ooperation'with a front contact 14. The neutral relay B is inclusive in the present instance of six switch arms designatedlS, 16, 17, 18, 19 and 20, respectively, the first of which is "adapted for cooperation with a front contact 15,

the second of which is adapted for cooperation with a back contact 16, the third of which is adapted for cooperation with a back contact 17, the fourth of which is adapted for cooperation with a front contact 18, the fifth of which is I adapted for cooperation with a front contact 19 and the sixth of which is adapted for cooperation with a front contact 20 The neutral relay C also is inclusive in the present instance of six switch arms designated 21, 22, 23, 24, and 26, respectively, the first of which is adapted for cooperation with a front contact 21 the second of which is adapted for cooperation with a back contact 22 the third of which is adapted for cooperation with a back contact 23 the fourth of which is adapted for cooperation with a front contact the fif h or" which is adapted for cooperation with a front contact 25, and the sixth of which is adapted for cooperation with a front contact 26 One end of the windin of the relay A is con nected by a conductor 2'7 with the switch arm 11 and the other end of said winding is connected by a conductor 28 with the switch arm 12; one end of the winding of the relay B is connected by a condoctor 29 with theswitch arm 1 and the other end of said winding is connected by a conductor 30 with the switch arm 14; one end of the winding of relay 0 is connected by a conductor 31 with switch arm 4, and the other end of said winding is connected by a conductor 82 with switch arm 19; one end of the winding of the relay A is connected by a conductor 33 with the contact 3 and also with the switch arm 10, and the other end or" said winding is connected by a conductor 34 with one end of the winding of the relay B, the other end of the winding of said last-mentioned relay being connected by a conductor 35 with the contact 6 and with the switch arm 15; one end of the winding of relay C is connected by a conductor 36 with the contact 9 and with the switch arm 21 while the other end of said winding is connected by a conductor 3'7 with one pole, in this instance the negative pole, of a suitable source of current such as a battery indicated at D. In addition, a conductor 34' connects the conductor 34 with the conductor 37.

A conductor 38 connects the contact 1% with the switch arm 13; a conductor 39 connects the contact 2 with the switch arm 3; a conductor 46 connects the contact 4 with the switch arm 18; a conductor 41 connects the contact 5 with the switch arm 6; a conductor 42 connects the contact 5 with the switch arm 2 and also with the contact 10 and the switch arm 20; a conductor 43 connects the contact 8 with the switch arm 9 a conductor 44 connects the contact 11 with the switch arm 16 and also with the contact 14 aconductor 45 connects the contacts 12 13 together and with J the switch arm 17; a conductor 46 connects the contact 15 with the contact 8 and also with the switch arm 26; a conductor 47 connects the contact 16 with the switch arm 22 and also with the contact 19 the contacts 17 18* are connected 7 together and to the switch arm 23 by a conductor 48; the contacts 20 26 21 and the switch arms 5 and 8 are connected by conductors 49 to the positive pole of the battery D; the contact 22 is connected by a conductor 59 with the switch arm 24 and one of the line wires n; the contact 23 is connected by a conductor 51 with the switch arm 25 and with the other of the line wires 22, and from the contacts 24 25 conductors 52, 53 lead to the device such as a telephone, a visual or audible signal, a power device or, in fact, any electrically operated device (not shown) to be controlled by the selector. 1

In addition to the switch arms 1, 2, and 3, the poralized relay A is inclusive of two additional switch arms a and I) having complemental front contacts a, b, the former of which is connected by a conductor 54 with the conductor 28 and the latter of which is connected by a conductor 55 with the conductor 27. Similarly, the relay B, in addition to the switch arms and contacts previously described, is inclusive of two additional switch arms 0 and d and complemental contacts 0, d, the former of which is connected by a conductor 56 with the conductor 30 and the latter of which is connected by a conductor 57 with the conductor 29. From the switch arm 0 a conductor 58 leads to and is connected with conductor 50, and from the switch arn d a conductor 59 leads to and is connected with the conductor 61, while from the switch arms a and b conductors 60, 61, respectively, lead to and are connected with the conductors 58 and 59, respectively.

Current for the line wires 11, :0 may be obtained from any desired source, a battery E being illustrated in the present instance as furnishing such current, while interposed in said line wires 11, p, between the battery and the selector, is a key or other suitable form of switch designated generally at F. Ihis switch in the present instance is inclusive of a pair of switch arms 62 and 63, to opposite sides of the first of which are disposed contacts 64 and 65, and to opposite sides of the latter of which are disposed contacts 66 and 67. From one pole of the battery E, the negative pole in this instance, a conductor 68 leads to and is connected to the arm While from the other pole of said battery a conductor 69 leads to and is connected with arm 63. lhe contacts 65 and 66 are connected together and with the line wire n by a conductor 70, while the contacts 64 and 67 are connected together and with the line wire 32 by a conductor 71.

Assuming that the switch arm 3 of relay A is moved into engagement with the contact 3 only when said relay is subjected to a current impulseof positive polarity; that the arm 6 of the relay B is moved into engagement with the contact 6 only when said relay is subjected to a current impulse of negative polarity, and that the arm 9 of relay C is moved into engagement with the contact 9 only when said relay is subjected to a current impulse of positive polarity, the operation of the present selector to establish a circuit between the line wires n, p and the conductors 52, 53 is as follows: The switch 36 is actuated to energize the relay A with current of positive polarity, i. e., the arms 62, 63 of said switch are moved into engagement with the contacts 65, 67, respectively. A circuit from the battery E through the relay A thus is completed as follows: from the positive side of the battery E through the conductor 69 to the switch arm 63, to the contact 6'7, to the conductor 71, to the line wire 50, to the conductor 51, to the contact 23 of the neutral relay C, to the switch arm 23, to the conductor 48, to the back contact 17 of the relay 3, to the switch arm 17, to the conductor 4", to the back contact 12 of the relay A to switch arm 12, to the conductor 28, through the coil of the relay A, to the conductor 27, to the switch 11, to the back contact 11, to the conductor 44, t0 the switch arm 16, to the back contact 16 to the conductor 47, to the switch arm 22, to the back contact 22 to the conductor 50, to the line wire n, to the conductor 70, to the contact 65, to the switch arm 62, and through the conductor 68 to the negative side of the battery.

Upon completion of the foregoing circuit the respective switch arms of the relay A are-moved into engagement with their complemental contacts, thus to close a local battery circuit fromv the battery D to the neutral relay A. If for any reason the relay A should become deenergized beforethe local battery circuit through the relay A is completed, the selector would not function properly. Therefore atlthe same time the line circuit above describedthroughthe relay A is completed another circuit is'also completed through said relay to hold same energized until the line circuit is opened. This holding circuit may be traced" as follows: from the line wire p through the conductor 51, to the conductor 59, to

the conductor 61, to the contact arm b, to the contact b, to the conductor 55, to the conductor 2'7, to the coil of the relay A, through said coil to the conductor 28, to the conductor -54, tothe contact a, to the switch arm a, to the conductor 60, to the conductor 58, to the conductor and to the line wire 11.

The local battery circuitthrough the relay A which is completed upon 'energization ofv the relay A maybe traced as follows: from the positive side of battery D to the conductor. 49, to the switch arm 5 of the relay B to the contact 5*, to the conductor 42, to the switch arm 2 of the relay A, to the contact 2, to the conductor 39, to the switch arm 3, to the contact 3?, to the conductor 33, through the coil of the relay A, to the conductor 34, to. the conductor 34 to the conductor 37vand to. the negative side of the battery D.

Upon energization of the relay A a circuit is completed to-enable energizationof the relay 3' tact 10, to the switch arm 10, to the conductor" 33, through the coil of the relay A to the con: ductor 34, to the conductor 34', and through the conductor 37 to the negative side ofthe battery D. Since the switch arm Got the relay B will be moved into engagement with the contact 6 only when current of negative polarity is supplied to said relay, it now becomes necessary in order to close the switch arm 6 with the contact 6 to actuate the switch F by moving the switch arms 62, and 63 into engagement with the contacts'64.

and 66 respectively When this is done a circuit from the line battery E through the relay B is completed as follows: from the negative side of the battery E through the conductor 68 to the switch arm 62, to the contact 64, to the conductor 71, to theline wire p, to the conductor 51, to the contact 23, to the switch arm 23, to the conductor 48, to the contact 17, to the switch arm 17, to the conductor 45, tothe contact 13, to the switch arm 13, tothe conductor 38, to the contact'l to the switch arm 1, to the conductor 29, through the coil of the relay B to the conductor 30, to :the switch arm 14, to the contact 14 to the conductor 44, to the switch arm 16, to the contact 16., to the the same time a, line circuit is completed to hold the foregoing circuit the relay B energized until the line circuit is opened, which circuit may be traced as follows:

from the line wire 1) to the conductor 51, to the conductor 59, to theswitch arm d, to the contact d; to the conductor 57, through the coil of the relay B tothe conductor 30, to the conductor 58,

to' the contact c, tothe switcharm c, to the condoctor 58-, to the conductor 50, and. to the line wire-n.

V The local batterycircuit when is tom-Paar,

from the batteryD through the relay B upon energization of therelay B may be traced as fol lows: from. thepositive side of the battery Dto the call of the relay B to the conductor '34, through the'conductor 34 to the conductor 3''! and thence to the negative side of the battery D. In order tohold the relay A energized whenv the relay B is energized, irrespective of energizatioriv and deenergization of the relays A and 13-,

completed asiollows: from" the positive side of the battery D to the conductor 49, to the contact 20 to the switcharm 20,"to the conductor 42, to the contact 10", to .the switch arm 10, to the conductor 33, through the coil of the relay A to the conductor 34, through the conductor 34 to the conductor 37 and thence to the negative side of the battery D. i a V It will be noted that the first locking circuit for relay A openswhen contact 55 of relay B opens, and that a'secon'd locking circuit for relay A :is closed when relay B becomes energized.

The neutral relaysA', B, C require an appr.e-

ciable time period to relase, howevenandfif a brief time interval elapses during which both locking circuits for relay A"are open, the front contact 1010 of relay A will remain closed and prevent improper. operation; In actual practice the contactsx5-5"! and 55 may be adjusted to have a small overlap so'that the release time of the ordinary direct current relay will be sufllcientto bridge the period during which relay A is deenergized, though relays A, B, and C may be slightly slow acting As explained above, both of the relays A and B are held closedand. the next operation-is to energize the relay C by a current of positive 190- larity in order to complete a circuit to the relay C. This is accomplished bya second time moving'the switch arms 62 and 63 into engagement with thecontacts65 and 6'7 respectivelyvto completea circuit as follows: from the positive side of thebattery E through the conductor69 to the switch arm 63,;to the conductor -71, to the line wire 1:, to the conductor 51, to the contact 23, to the switch arm" 23, to the conductor 48, to the contact 18 to the switch arm 18, to the conductor 40', to the contact 4, to theswitch arm 4,

to. the conductor 31, through the coil of the relay Cto the conductor 32, to the switch arm 19, to the contact19 5'to the conductor 47, to the switch arm 22, to the contact 22, to the conductor 50, to the line wire n, to the conductor '70, to the contact 65, to the switch arm 62, and through the conductor 68 to the negative side of the batt ry,

Upon completion of the foregoing circuit a local battery circuit through the relay, C" is completed as follows: from the positive of the battery D tothe conductor-49, to the switch arm 8, to the contact ,8, through the conductor 43 to the switch arm 9, to the, contact ,9, to the cona localbattery holding circuit for the relay A is ductor 36, through the coil of the relay C, to the conductor 37 and to the negative side of the battery.

- To hold the relay B energized upon completion of the circuit through the relay C as just described a local battery circuit is completed as fol lows: from the positive side of the battery D to the conductor 49, to the contact 26*, to the switch arm 26, to the conductor 46, to the contact 15 to the switch arm 15, to the conductor 35, through the coil of the relay B to the conductor 34, to the conductor 34' to the conductor 3'7, andthence to the negative side of the battery D.

In order to prevent deenergization of the relay B upon deenergization of the relays B and C a circuit is completed as follows: from the positive side of the battery D through the conductor 49 to the switch arm 8, to the contact 8 ,through the conductor 46, to the contact 15*, to the switch arm 15, to the conductor 35, through the coil of the relay B, to the conductor 34, through the conductor 34 to the conductor 37, and thence to the negative side of the battery D. As explained in connection with relay A, the parts are constructed in such manner that relay B does not open its front contacts even though a brief period elapses after the opening of the first locking circuit and the closing of the second locking circuit for this relay.

Upon energization of the relay C the switch arms 24 and 25 are moved into engagement with the contacts 24 and 25 respectively and a circuit from the line wires pn is. closed as follows: from the line wire p to the conductor 51, to the switch arm 25, to the contact 25 to the conductor 53, through whatever instrument is interposed between the conductors 53 and 52 through the conductor 52 to the contact 24 to the switch arm 24, to the conductor 50 and thence to the line wire 11.. As will be understood of course this lastmentioned circuit may receive its energy from a local battery instead of from the line wires 11., p.

As will be further understood deenergization of a the respective relays of the selector and restoration of the latter to normal status may be effected in any desired manner.. For example a suitable switch or relay indicated at G, under thezcontrol of whatever instrument or device is interposed in the circuit comprised by the conductors 52 and 53, may be included in either of the conductors 37 or 49, the same being illustrated as being.

included in this instance in the conductor 49.

In order to explain the operation of the apparatus in response to a combination different from that to which the selector is intended to respond, I will assume that the switch F is operated to deliver to the line wires n, p, a code combination of two positive impulses followed by a negative impulse. Assuming also that the apparatus occupies the normal condition illustrated in the drawing, the first impulse of this code energizes relay A and switch arm 3 moves into engagement with contact 3*. The pick-up circuit previously traced for relay A then becomes closed and relay A closes its front contacts, thereby completing-its stick circuit overits own front contact l0--l0 and back contact 5-5 of relay B, as explained hereinbefore. When relay A opens at the conclusion of the first impulse, relay A remains energized.

When the second impulse of the code is im pressed upon the line wires 11., p, relay B becomes energized, but since this impulse is of positive polarity, contact 6-6 does not close; 'RelayB therefore remains deenergized. Under these conditions, one branch for the stick circuit of relay A is open at back contact 5--5 of relay B, and the other branch of this stick circuit is open at front contact 20--20 of relay B, so relay A becomes deenergized. At the conclusion of this second impulse, relay B again becomes deenergized;

Since relay A is now deenergized, the third impulse of the code, now supplied to the line wires 11, p, energizes relay A, but this impulse is of negative polarity so contact 33 does not close. This impulse therefore does not affect the remaining apparatus, and when the relay A becomes deenergized at the conclusion of the third impulse, the apparatus is restored to the normal condition.

It will be apparent from the foregoing, that the selector operates to supply energy to the circuit 52, 53 only in response to the particular code for which the selector is designed and can not be actuated improperly by another code.

The number of polarized relays and associated neutral relays contained in the selectors determines the maximum number of selectors which may be included for operation in any given line circuit. Three polarized relays A, B and C affords opportunity for eight different combinations of such relays and therefore it is possible simply by an interchange of said relays or by substituting positive for negative and negative for positive relays, to embody eight such selectors in a system for individual selector operation by a single switch F. The eight combinations available with three impulses of two kinds are indicated in the following table:

.By adding a fourth polarized relay and an associated neutral relay the number of possible polarity combinations will be increased to sixteen and the number of selectors which may be included in a system for selective operation by a single switch F will be doubled. In other words each time an additional polarized relay and an associated neutral relay is added to the selector the number of possible polarity combinations is doubled so that by the provision of selectors embodying a minimum number of relays, a maximum number of electrical devices may be controlled from a single point by means of a single switch device such as the switch F herein illustrated.

From the foregoing description it is thought that the features and advantages of the invention will be readily apparent to those skilled in the art and it will of course be understood that changes in form, proportion and minor details l and responsive thereto irrespective of its character, a second relay individual to each code element and selectively responsive to the character of said element, means allocated to each code element and controlled by both of the associated said relays for placing the relays individual to the next irrespective of its character, a series of register relays one for each counting relay, means controlled by each counting relay for operating the corresponding register relay only when the corresponding code element is of selected character;

and a'control circuit for each counting relay except the first, including a front contact of the next preceding register relay, whereby the operation of the final counting relay is effected only when the series of code elements is of the particular code pattern to which said receiver is adjusted.

3. A code receiver responsive to a code of a fixed number of elements each comprising an impulse of a selected one of a plurality of different characters of current, comprising ,a series of counting relays each responsive to a particular code element irrespective of its character, a contral circuit normally connected to the first relay of said series, a code register relay for eachcounting relay, means controlled by each countingrelay for operating the corresponding register relay only if the corresponding code element is of a selected character, and means controlled by each register relay for disconnecting the corresponding counting relay from said control circuit, and for connecting the next succeeding counting relay thereto, whereby the reception of each consecutive code element is dependent upon the particular character of the next preceding code element.

- H. L. BLACK. 

